\chapter{Further work}
In this chapter some suggestions on further work on the subject of irreversibility in turbulent combustion are given.

\begin{enumerate}

	\item The data set for the DLR-A Flame (22\% $CH_4$, 33\% $H_2$, 45\% $N_2$), which is also available from the TNF experimental data archive \cite{TNFdata}, has higher resolution than the data set used in this thesis. The method of implementing curvefitted functions of $\tilde{\xi}$ for this flame could yield more accurate results. The data set contains data for a wider range of the mixture fraction because of the different composition  of the flame. This improves the accuracy of the curvefits and thus the method presented in this thesis may yield more accurate results.

	\item Som and Datta (2005) \cite{Som2005} suggest oxygen enrichment and combustion staging as methods of improving the second law efficiency in combustion. Oxygen enrichment raises the stoichiometric flame temperature and from a bulk exergy viewpoint it is known that this increases the exergy efficiency. In the entropy production term from chemical reaction, Eq. \ref{eq:chementropy}, higher stoichiometric flame temperature also lowers the contribution of this mechanism to exergy destruction.

	\item The exergy efficiency of other flame configurations such as a catalytic combustor, oxyfuel combustion, chemical looping combustion and PDE-engines are possibly topics to study.

	\item The prescribed PDF method is simple to use and recommended for computation on turbulent diffusion flames

	\item In this thesis only a $H_2$-flame has been studied. The prescribed PDF method assumes that $Le=1$, which is a reasonable approximation for turbulent combustion of hydrocarbon fuels, but not necessarily true for turbulent nonpremixed $H_2$-flames. Other methods like joint PDF or the Flamelet model should also be considered. Computational methods where the scalar dissipation rate can be readily found are preferred. Simulations in FlameMaster \cite{FlameMaster} where planned for this report, but could not be performed due to lack of time.

\end{enumerate}

The results in this report where found from a simulation code developed by the author. This code is attached in Appendix \ref{sec:mapleroutine}. The code may possibly contain errors.